What to replace an Adcom amp with?

I have an Adcom 5503 that is probably in need of repair or refurbishment.  There is a buzz coming through my left and right channels (not my center) that I have traced back to the 5503 and it is starting to get very hot even while listening at low to moderate levels.  The 5503 powers my front three channels and a 555 II powers my two rear channels.  My speakers are four KEF Reference 201, a 202C as my center channel and a sub.  I have been extremely happy with my two Adcom amps and really enjoy the listening experience.  I listen to music and watch movies on this system.  I listen to a lot of 5.1 music on SACD, DVD-A, and Blu-Ray Audio.  I've thought about just getting a new 5 channel Adcom or find a used 5503 but before I did, I thought I would ask some advice from this forum.  Any thoughts on what amp would be most "Adcom-like" or would give me an improvement in the listening experience?  The KEFs are a little bright so I definitely don't want to get something that would accentuate that.  Again, I would really be interested in everyone's opinion.  Stick with Adcom or change to a different brand altogether?  As far as budget, I would like to keep it at $2-3K if possible and I am not afraid of used equipment at all.  Thanks in advance.  Dave